The Indian Reorganization Act was a Congressional law enacted in 1934 which affected how AmericanIndianTribes governed themselves, affected the distributions of Indian lands, and redefined how Indians managed assets held by the tribe. In general, Indian tribes were required to create a Tribal Council and authorize that Council to act on behalf of the Tribe. Until this point, the US Government had no official person to work with for any given tribe, and often was placed in the position of finding out that someone who represented himself as "leader" or "spokesperson" was in fact, neither.

The act reversed the Dawes Act, and returned individually held land to common holdings for the Tribe. The goal of this aspect of the Act was to reduce land loss by individuals who sold off parcels of tribal land "in the name of the Tribe", while generally keeping monies earned from the sale private.

It also included provisions to terminate status of "Reservations", and in turn terminate or renegotiate the status of "Dependent Domestic Nations" within the United states. Due to the Act, the United States Government reduced or fully dismantled official recognition of 61 Nations.

Many States have challenged the Constitutionality of the IRA, specifically the "land to trust" repatriation aspects.